Golf club head and method for shifting the club head center of gravity

ABSTRACT

A golf club head and a method for shifting the club head center of gravity. The golf club head includes a body having a front face, a back face, a heel end, a toe end, and a sole extending between lower portions of the heel and the toe ends. The golf club head also has a top rail extending between upper portions of the heel and toe ends and at least one cavity extending from the back surface into the body. Three or four weighting elements are attached to the body to shift the club head center of gravity in accordance with the desired performance of an individual golfer. The weighting elements are formed of a material which has a different density than the material forming the body.

BACKGROUND OF THE INVENTION

The present invention relates, in general, to golf equipment and, more particularly, to a golf club head and a method for shifting the club head center of gravity.

An important factor governing the distance and accuracy of a golfer's shot is the amount of energy transferred from the golf club head to a golf ball when it impacts the golf ball. Ideally, the point of impact on the face of the golf club head is below the center of gravity of the golf club head and the point of impact on the golf ball is below the center of gravity of the golf ball. In addition, a theoretical plane containing the impact point on the golf club head, the center of gravity of the golf club head, and the center of gravity of the golf ball should be in alignment with the intended path of travel of the golf ball. When these conditions are met, the golf club head is properly aligned.

To help golfers achieve proper alignment, golf club manufacturers have concentrated a relatively large mass of the golf club head in its sole. Although this configuration has made it easier for a golfer to place the center of gravity of the golf club head below the center of gravity of the golf ball, it is still difficult for a golfer to achieve perfect alignment. For example, the club head may be square immediately prior to impact with a golf ball but, at impact, the golf club head may be moved so that the actual point of impact with the golf ball is toward either the toe end or the heel end of the club head. This results in improper alignment because the club head becomes “twisted” to an out-of-square position which results in less than the maximum amount of energy being transferred to the golf ball.

It should be understood that the term “twisted” is used here to define a rotation of the club head at the point of impact with a golf ball about an axis which passes through the center of gravity of the club head and is parallel to the axis of the golf club shaft. To dampen or reduce the effects caused by twisting of the club head, golf club manufacturers have placed relatively large concentrations of mass in the heel and toe ends of the club head to increase the club head moment of inertia and thereby maximize energy transfer from the club head to the golf ball. These techniques have improved the ability of golfers to increase the consistency with which they properly align their golf club heads.

SUMMARY OF THE INVENTION

The present invention provides a golf club head and a method for shifting the center of gravity of the golf club head. In accordance with one aspect, the present invention includes a club head comprising a body having a front face for impacting a golf ball, a back face, a heel end, a toe end, a sole, and a top rail. A cavity having a bottom surface extends from the back face into the body. The body is formed of a first material having a predetermined density. The cavity has a first wall adjacent the sole, a second wall adjacent the top rail, and a third wall adjacent the toe end. The first wall cooperates with the second wall to form a first intersection, and the first wall cooperates with the third wall to form a second intersection. The second wall and the third wall cooperate to form a third intersection. A first weighting element is attached to the body adjacent the first intersection, a second weighting element is attached to the body adjacent the second intersection, and a third weighting element is attached to the body adjacent the third intersection. The first, second and third weighting elements are each formed of a second material which has a predetermined density that is different than the predetermined density of the first material.

In accordance with another aspect, the present invention provides a golf club head comprising a body having a front face for impacting a golf ball, a back face disposed rearwardly of the front face, a heel end and a toe end. The body is formed of a first material having a predetermined density. A perimeter weighting element protrudes rearwardly away from the front face defining a primary cavity in the back face. The perimeter weighting element includes a top rail extending between the heel and toe ends along an upper portion of the body, and a sole extending between the heel and toe ends along a lower portion of the body. A means for shifting the club head center of gravity is coupled to the golf club head and includes a first weight attached to the body adjacent an intersection of the sole and the heel end of the body, a second weight attached to the body adjacent an intersection of the sole and toe end of the body, and a third weight attached to the body adjacent an intersection of the top rail and the toe end of the body. The first, second and third weights are each formed of a second material which has a predetermined density that is different than the predetermined density of the first material.

In accordance with a further aspect, the present invention provides a method for adjusting the center of gravity of a golf club head by providing a golf club head comprising a body having a front face for impacting a golf ball, a back face, a heel end, a toe end, a sole, and a top rail. The body is formed of a first material having a predetermined density. A cavity having a bottom surface and at least three walls is formed in the back face. The first wall and the second wall form a first intersection, the first wall and of the third wall form a second intersection, and the second wall and the third wall form a third intersection. The center of gravity of the golf club head is shifted by attaching first, second and third weighting elements to the body adjacent the first, second, and third intersections, respectively. The first, second and third weighting elements are each formed of a second material which has a predetermined density that is different than the predetermined density of the first material.

DESCRIPTION OF THE DRAWINGS

The present invention will be better understood from a reading of the following detailed description, taken in conjunction with the accompanying drawing figures, in which like reference numbers designate like elements and in which:

FIG. 1 is a view of a golf club including an iron-type golf club head in accordance with one embodiment of the present invention;

FIG. 2 is an enlarged back view of the iron-type golf club head shown in FIG. 1;

FIG. 3 is an enlarged back view of an iron-type golf club head in accordance with another embodiment of the present invention;

FIG. 4 is a rear perspective view of an iron-type golf club head in accordance with a further embodiment of the present invention;

FIG. 5 is toe end view of the iron-type golf club head of FIG. 4;

FIG. 6 is a heel end view of the iron-type golf club head of FIG. 4;

FIG. 7 is a bottom view of the iron-type golf club head of FIG. 4; and

FIG. 8 is a rear perspective view of an iron-type golf club head in accordance with another embodiment of the present invention.

DESCRIPTION OF THE INVENTION

FIG. 1 shows a golf club 10 having an iron-type golf club head 12 connected to one end of a golf club shaft 14 with a grip 16 mounted on an opposing end of golf club shaft 14. Suitable materials for golf club shaft 14 include steel and graphite. Club head 12 has a cavity back 18 in which center of gravity shifting means 20 is disposed.

Referring now to FIG. 2, an enlarged back view of iron-type golf club head 12 is illustrated. Iron-type golf club head 12 includes a body 24 and a hosel 26, which has a cylindrical bore 28 for receiving one end of golf club shaft 14. The body 24 has a heel end 30 spaced apart from a toe end 32. A sole 34 extends from a lower portion of heel end 30 to a lower portion of toe end 32, and a top rail 36 extends from an upper portion of heel end 30 to an upper portion of toe end 32. Body 24 has a front face (not shown) for impacting a golf ball that extends between heel end 30 and toe end 32 along a frontal portion of body 24. Body 24 also has a back face 38 that extends between heel end 30 and toe end 32 along a back or rear portion of body 24. Hosel 26 includes a neck 40 connected to heel end 30 of body 24. Club head 12 may be formed by casting, machining from solid castings or the like. Body 24 and hosel 26 are formed of a first material which has a predetermined density. Suitable materials for body 24 and hosel 26 include, but are not limited to, stainless steel, titanium, aluminum, nickel, alloys of titanium, alloys of aluminum, alloys of nickel, and the like.

A cavity 42 extends from back face 38 into body 24. Cavity 42 has a bottom surface 44 and a plurality of walls 46, 48, and 50, in which wall 46 is adjacent sole 34, wall 48 is adjacent top rail 36, and wall 50 is adjacent an edge 52 of toe end 32. A portion of wall 46 near heel end 30 cooperates with a portion of wall 48 near heel end 30 to form an intersection 54. A portion of wall 46 near toe end 32 cooperates with a portion of wall 50 near a lower portion of toe end 32 to form an intersection 56. A portion of wall 48 near toe end 32 cooperates with a portion of wall 50 near a top portion of toe end 32 to form an intersection 58. Thus, in this embodiment, cavity 42 has a generally triangular shape. Cavity 42 may be formed during the process of casting club head 12. Golf club head 12 has an unshifted center of gravity located at a point indicated by reference number 59.

Weighting elements 60, 62, and 64 comprise the center of gravity shifting means 20 and are attached to body 24 adjacent intersections 54, 56, and 58, respectively. The weighting elements 60, 62, 64 may also be referred to as weights. Suitable methods for fastening weighting elements 60, 62, and 64 to body 24 include welding, using screws, or using an adhesive material. The weighting elements 60, 62, 64 are formed of a second material which has a predetermined density that is different (i.e. greater or less) than the predetermined density of the material forming the body 24. Suitable materials for the weighting elements 60, 62, 64 include tungsten and polyurethane.

To lower the launch angle and increase the backspin on a golf ball, the weighting elements 60, 62, 64 are selected such that weighting elements 60 and 62 have substantially equal volumes and the weighting element 64 is selected to have a volume that is greater than the volumes of each of the weighting elements 60 and 62. Therefore, the weighting elements 60, 62 will have the same mass while the weighting element 64 will have greater mass than either of the weighting elements 60, 62. Preferably, the volume of weighting element 64 is selected to be at least five times greater than the volumes of weighting elements 60 and 62. By way of example, the ratio of the volumes of weighting element 60 to weighting element 62 to weighting element 64 is 1.5 to 1.5 to 10 (i.e., 1.5:1.5:10). This produces a golf club head with a high center of gravity relative to the unshifted center of gravity located at point 59.

To raise the launch angle and increase the backspin on a golf ball, the weighting elements 60, 62, 64 are selected such that weighting elements 60 and 62 have substantially equal volumes while the weighting element 64 is selected to have a volume that is less than the volumes of each of the weighting elements 60 and 62. Therefore, the weighting elements 60, 62 have the same mass while the weighting element 64 will have less mass than either of the weighting elements 60, 62. Preferably, the volume of weighting element 64 is selected to be one-tenth the volumes of weighting elements 60 and 62. By way of example, the ratio of the volumes of weighting element 60 to weighting element 62 to weighting element 64 is 10 to 10 to 1 (i.e., 10:10:1). This produces a golf club head with a low center of gravity relative to the unshifted center of gravity located at point 59.

To lower the launch angle slightly and “hook” a golf ball to the left, the weighting elements 60, 62, 64 are selected such that weighting elements 62 and 64 have substantially equal volumes and the weighting element 60 is selected to have a volume that is greater than the volumes of each of the weighting elements 62 and 64. Therefore, the weighting elements 62, 64 will have the same mass while the weighting element 60 will have greater mass than either of the weighting elements 62, 64. Preferably, the volume of weighting element 60 is selected to be at least 1.8 times the masses of weighting elements 62 and 64. By way of example, the ratio of the volumes of weighting element 60 to weighting element 62 to weighting element 64 is 10 to 5.5 to 5.5 (i.e., 10:5.5:5.5). This produces a golf club head with a center of gravity near the heel end relative to the unshifted center of gravity located at point 59.

To raise the launch angle slightly and “fade” a golf ball to the right, the weighting elements 60, 62, 64 are selected such that weighting elements 62 and 64 have substantially equal volumes and the weighting element 60 is selected to have a volume that is less than the volumes of each of the weighting elements 62 and 64. Therefore, the weighting elements 62, 64 will have the same mass while the weighting element 60 will have less mass than either of the weighting elements 62, 64. Preferably, the volumes of weighting elements 62 and 64 are selected to be at least eight times the volume of weighting element 60. By way of example, the ratio of the volume of weighting element 60 to weighting element 62 to weighting element 64 is 1 to 8.6 to 8.6 (i.e., 1:8.6:8.6). This produces a golf club head with a center of gravity near the toe end relative to the unshifted center of gravity located at point 59.

Referring now to FIG. 3, an enlarged back view of iron-type golf club head 72 in accordance with another embodiment of the present invention is illustrated. Like iron-type golf club head 12, iron-type golf club head 72 includes body 24 and hosel 26 having cylindrical bore 28 for receiving one end of golf club shaft 14. The body includes heel end 30, toe end 32, sole 34, top rail 36, back face 38, and a center of gravity at point 59. However, a cavity 74 extending from back face 38 into body 24 has a generally quadrilateral shape. Cavity 74 has a bottom surface 76 and a plurality of walls 78, 80, 82, and 84, in which wall 78 is adjacent sole 34, wall 80 is adjacent top rail 36, wall 82 is adjacent heel end 30, and wall 84 is adjacent an edge 52 of toe end 32. A portion of wall 78 near heel end 30 cooperates with a lower portion of wall 82 to form an intersection 86. A portion of wall 78 near toe end 32 cooperates with a portion of wall 84 near a lower portion of toe end 32 to form an intersection 88. A portion of wall 80 near toe end 32 cooperates with an upper portion of wall 84 near toe end 32 to form an intersection 90. A portion of wall 80 near heel end 30 cooperates with an upper portion of wall 82 to form an intersection 92. Cavity 74 may be formed during the process of casting club head 72. Alternatively, cavity 74 may be formed by machining.

Similar to iron-type golf club head 12, weighting elements 60, 62, and 64 are attached to body 24 adjacent intersections 86, 88, and 90, respectively. If desired, an additional weighting element 66 may be attached to body 24 adjacent intersection 92. Selecting the masses of weighting elements 60 and 62 to be substantially the same and the mass of weighting element 64 to be greater than the masses of weighting elements 60 and 62 gives golf club head 72 a high center of gravity relative to the unshifted center of gravity at point 59 of golf club head 72, thereby lowering the launch angle and increasing the backspin on the golf ball. Selecting the masses of weighting elements 60 and 62 to be substantially the same and the mass of weighting element 64 to be less than the masses of weighting elements 60 and 62 raises the launch angle, increases the backspin on the golf ball, and gives golf club head 72 a lower center of gravity relative to the unshifted center of gravity at point 59 of golf club head 72. Selecting the masses of weighting elements 62 and 64 to be substantially the same and the mass of weighting element 60 to be greater than the masses of weighting elements 62 and 64 moves the center of gravity of golf club head 72 toward heel end 30 relative to the unshifted center of gravity at point 59 of golf club head 72, which slightly lowers the launch angle and “hooks” a golf ball to the left. Selecting the masses of weighting elements 62 and 64 to be substantially the same and the mass of weighting element 60 to be less than the masses of weighting elements 62 and 64 moves the center of gravity of golf club head 72 towards toe end 30 relative to the unshifted center of gravity at point 59 of golf club head 72, which slightly raises the launch angle and “fades” a golf ball to the right. Exemplary masses are the same as those described with reference to FIG. 2.

FIGS. 4, 5, 6, and 7 are various views of an iron-type golf club head 100 in accordance with a further embodiment of the present invention. It should be understood that golf club head 100 is suitable for use as the golf club head for golf club 10, i.e., golf club head 100 may be used in place of golf club head 12. Iron-type golf club head 100 includes a body 102 and a hosel 104, which has a cylindrical bore 106 for receiving one end of a golf club shaft such as, for example, golf club shaft 14 shown in FIG. 1. Body 102 has a heel end 108 spaced apart from a toe end 110. Body 102 also has front face 118 (shown in FIGS. 5 and 6) for impacting a golf ball that extends between heel end 108 and toe end 110 along a frontal portion of body 102. Disposed rearwardly of the front face 118 is a back face 112. Hosel 104 includes a neck 114 connected to heel end 108 of body 102. Like club head 10, club head 100 is preferably cast from stainless steel. Suitable materials for club head 12 include, but are not limited to, stainless steel, titanium, aluminum, nickel, alloys of titanium, alloys of aluminum, alloys of nickel, and the like.

Perimeter weighting element 116 protrudes rearwardly from front face 118 and defines a cavity 120 in back face 112. Perimeter weighting element 116 includes a top rail 122 and a sole 124. Primary cavity 120 is defined at its upper extremity by top rail 122 and at its lower extremity by sole 124. Top rail 122 extends between heel and toe ends 108 and 110, respectively, along an upper portion of body 102 and sole 124 extends between heel and toe portions 108 and 110, respectively, along a lower portion of body 102. Perimeter weighting element 116 also includes an upper toe weight 126 adjacent toe end 110 of top rail 122, a lower toe weight 128 adjacent toe end 110 of sole 124 and a lower heel weight 130 adjacent heel end 108 of sole 124. Toe end 110 of body 102 has a back edge 132 that is indented toward front face 118 between top rail 122, and sole 124 separating upper toe weight 126 from lower toe weight 128. Golf club head 100 has an unshifted center of gravity at a point indicated by reference number 127.

Upper and lower toe weights 126 and 128, respectively, and lower heel weight 130 provide club head 100 with resistance to a twisting movement about a vertical axis through body 102 as a result of front face 118 impacting a golf ball near heal end 108 or toe end 110 of body 102. Sole 124 has a lower trailing edge 134 that includes an indentation 135 (shown in FIG. 7) between lower toe and heel weights 128 and 130, respectively. Located adjacent lower trailing edge 134 of sole 124 is a lower backsurface 136 of perimeter weighting element 116. Lower backsurface 136 preferably slopes upwardly and inwardly from trailing edge 134 toward front face 118. Lower backsurface 136 merges with a lower inner surface 138 of perimeter weighting element 116 along an upper trailing edge 140 of sole 124. Indentation 135 and the sloping orientation of lower backsurface 136 serve to redistribute material in body 102 in a manner that increases the relative sizes of lower heel weight 130 and lower toe weight 128, thereby increasing the resistance of club head 100 to the above-mentioned twisting movement.

Primary cavity 120 defined by perimeter weighting element 116 has a bottom surface 142 on which an interior wall 144 is formed integrally. Interior wall 144 extends from an end 146 located adjacent heel end 108 through primary cavity 120 between top rail 122 and sole 124 to another end 148 located adjacent toe end 110. Ends 146 and 148 of interior wall 144 are integrally connected to perimeter weighting element 116 adjacent heel and toe ends 108 and 110, respectively, defining a secondary cavity 150 within primary cavity 120. Inner surface 152 of perimeter weighting element 116 is disposed between ends 146 and 148 of interior wall 144 and forms a lower extremity of secondary cavity 150. An inner surface 152 of interior wall 144 forms an upper extremity of secondary cavity 150. Interior wall 144 has a height dimension that varies between ends 146 and 148. It should be understood that the height dimension of interior wall 144 is greater at end 148 than at end 146. In other words, the height dimension of interior wall 144 is greater near toe end 110 than near heel end 108.

A weight adjustment member 154 (partially broken away in FIG. 4) having a predetermined volume is disposed in secondary cavity 150 and is secured therein by a suitable adhesive such as, for example, epoxy. Weight adjustment member 154 is selected from a plurality of weight adjustment members (not shown) that have the same predetermined volume but have different densities and thus different weights. This plurality of weight adjustment members preferably covers a range from about four grams to about thirty grams in one gram increments. This range of weights should be sufficient to cover different shaft lengths and different types of shafts that may be attached to club head 100. Therefore, the desired weight of club head 100 may be adjusted without changing the predetermined volume of weight adjustment member 154. By selecting a weight adjustment member 154 of proper weight, manufacturing tolerances can be overcome and the swingweight of a golf club may be adjusted. Weight adjustment member 154 is preferably formed of plastic. Since weight adjustment member 154 is located near the center of gravity of club head 100, the club head center of gravity will not change significantly when selecting any of the plurality of weight adjustment members.

Region 156 within primary cavity 120 that is adjacent lower heel weight 130 is adapted to receive a weighting element 162. Likewise, region 158 of primary cavity 120 that is adjacent lower toe weight 128 is adapted to receive a weighting element 164, and region 160 of primary cavity 120 that is adjacent upper toe weight 126 is adapted to receive a weighting element 166.

Weighting elements 162, 164, and 166 are attached to the body 102 within cavity 120 at regions 156, 158, and 160, respectively, and cooperate to shift the center of gravity of golf club head 100. Selecting the masses of weighting elements 162 and 164 to be substantially the same, and the mass of weighting element 166 to be greater than the masses of weighting elements 162 and 164, gives golf club head 100 a high center of gravity relative to the unshifted center of gravity located at point 127 which lowers the launch angle and increases the backspin on the golf ball. Selecting the masses of weighting elements 162 and 164 to be substantially the same and the mass of weighting element 166 to be less than the masses of weighting elements 162 and 164 raises the launch angle, increases the backspin on the golf ball, and gives golf club head 100 a low center of gravity relative to the unshifted center of gravity at point 127 of golf club head 100. Selecting the masses of weighting elements 164 and 166 to be substantially the same and the mass of weighting element 162 to be greater than the masses of weighting elements 164 and 166 moves the center of gravity of golf club head 100 toward heel end 108 relative to the unshifted center of gravity at point 127 of golf club head 100, which slightly lowers the launch angle and “hooks” a golf ball to the left. Selecting the masses of weighting elements 164 and 166 to be substantially the same and the mass of weighting element 162 to be less than the masses of weighting elements 164 and 166 moves the center of gravity of golf club head 100 toward toe end 110 relative to the unshifted center of gravity at point 127 of golf club head 100, which slightly raises the launch angle and “fades” a golf ball to the right. Exemplary masses are the same as those described with reference to FIGS. 2 and 4.

Referring now to FIG. 8, a back view of an iron-type golf club head 200 in accordance with another embodiment of the present invention is shown. Iron-type golf club head 200 is similar to iron-type golf club head 100, except that it does not include the interior wall 144, the secondary cavity 150 and the weight adjustment member 154. Otherwise, the description of iron-type golf club head 100 applies to iron-type golf club head 200. Thus, iron-type golf club head 200 includes body 102, hosel 104, heel end 108, toe end 110, back face 112, perimeter weighting element 116, front face 118, cavity 120, sole 124, an unshifted center of gravity at point 127, upper toe weight 126, lower toe weight 128, lower heel weight 130, back edge 132, lower trailing edge 134, lower backsurface 136, indentation 135, regions 156, 158, and 160, and weighting elements 162, 164, and 166.

By now it should be appreciated that a golf club having a club head in which the center of gravity can be shifted, i.e., a club head having a shiftable center of gravity, and a method for manufacturing the club head have been provided. Weighting elements are placed on the club head in a configuration to shift its center of gravity. An advantage of this configuration is that it allows the launch angle of a golf ball impacted by the club head to raised or lowered while increasing the backspin on the golf ball. Alternatively, the weighting elements can be positioned to raise or lower the launch angle of the golf ball while directing it to the left or to the right. Thus, shifting the center of gravity of the club head allows golfers to control the direction and distance a golf ball travels. In addition, before shifting of the club head center of gravity, the mass of the club head is less than its final mass. Shifting the club head center of gravity by utilizing the weighting elements of the present invention adjusts the mass of the club head to the desired final mass.

Although certain preferred embodiments and methods have been disclosed herein, it will be apparent from the foregoing disclosure to those skilled in the art that variations and modifications of such embodiments and methods may be made without departing from the spirit and scope of the invention. For example, the golf club head may be manufactured such that its mass is less than its final mass. Adjusting or shifting the center of gravity with weighting elements tunes the mass of the golf club head and gives it the desired final mass. It is intended that the invention shall be limited only to the extent required by the appended claims and the rules and principles of applicable law. 

1. A golf club head comprising: a body formed of a first material which has a predetermined density, the body having a front face for impacting a golf ball, a back face, a heel end, a toe end, a sole and a top rail; a cavity extending from the back face into the body, the cavity having a bottom surface and first, second, and third walls, the first wall being adjacent the sole, the second wall being adjacent the top rail, and the third wall being adjacent the toe end; the first wall cooperating with the second wall to form a first intersection, the first wall cooperating with the third wall to form a second intersection, and the second wall and the third wall cooperating to form a third intersection; a first weighting element attached to the body adjacent the first intersection, a second weighting element attached to the body adjacent the second intersection, and a third weighting element attached to the body adjacent the third intersection; and the first, second and third weighting elements each being formed of a second material which has a predetermined density that is different than the predetermined density of the first material.
 2. The golf club head of claim 1, wherein the predetermined density of the second material is greater than the predetermined density of the first material.
 3. The golf club head of claim 1, wherein the predetermined density of the second material is less than the predetermined density of the first material.
 4. The golf club head of claim 1, wherein the first and second weighting elements have substantially equal volumes and wherein the third weighting element has a volume that is greater than the volumes of each of the first and second weighting elements.
 5. The golf club head of claim 1, wherein the first and second weighting elements have substantially equal volumes and wherein the third weighting element has a volume that is less than the volumes of each of the first and second weighting elements.
 6. The golf club head of claim 1, wherein the second and third weighting elements have substantially equal volumes and wherein the first weighting element has a volume that is greater than the volumes of each of the second and third weighting elements.
 7. The golf club head of claim 1, wherein the second and third weighting elements have substantially equal volumes and wherein the first weighting element has a volume that is less than the volumes of each of the second and third weighting elements.
 8. The golf club head of claim 1, wherein the cavity has a generally triangular shape.
 9. The golf club head of claim 1, wherein the cavity has a generally quadrilateral shape.
 10. The golf club head of claim 1, further comprising an interior wall extending through the cavity from the heel end to the toe end.
 11. A golf club head comprising: a body formed of a first material which has a predetermined density, the body having a front face for impacting a golf ball, a back face disposed rearwardly of the front face, a heel end, and a toe end, the club head having a center of gravity; a perimeter weighting element protruding rearwardly away from the front face defining a cavity in the back face, the perimeter weighting element including a top rail extending between the heel and toe ends along an upper portion of the body, the perimeter weighting element also including a sole extending between the heel and toe ends along a lower portion of the body; means for shifting the center of gravity of the club head including a first weight attached to the body adjacent an intersection of the sole and the heel end of the body, a second weight attached to the body adjacent an intersection of the sole and toe end of the body, and a third weight attached to the body adjacent an intersection of the top rail and the toe end of the body; and the first, second and third weights each being formed of a second material which has a predetermined density that is different than the predetermined density of the first material.
 12. The golf club head of claim 11, wherein the first and second weights have substantially equal masses and wherein the third weight has a mass that is less than the masses of either of the first and second weights.
 13. The golf club head of claim 11, wherein the first and second weights have substantially equal masses and wherein the third weight has a mass that is greater than the masses of either of the first and second weights.
 14. The golf club head of claim 11, wherein the second and third weights have substantially equal masses and wherein the first weight has a mass that is less than the masses of either of the second and third weights.
 15. The golf club head of claim 11, wherein the second and third weights have substantially equal masses and wherein the first weight has a mass that is greater than the masses of either of the second and third weights.
 16. The golf club head of claim 11, wherein the predetermined density of the second material is greater than the predetermined density of the first material.
 17. The golf club head of claim 11, wherein the predetermined density of the second material is less than the predetermined density of the first material.
 18. The golf club head of claim 11, wherein the cavity has a generally triangular shape.
 19. The golf club head of claim 11, wherein the cavity has a generally quadrilateral shape and further comprising a fourth weight attached to the body adjacent an intersection of the top rail and the heel end of the body.
 20. A method for adjusting the center of gravity of a golf club head, comprising: providing a golf club head including a body formed of a first material which has a predetermined density, the body having a front face for impacting a golf ball, a back face, a heel end, a toe end, a sole, and a top rail; forming a cavity in the back face, the cavity having a bottom surface and at least three walls, wherein a first portion of the first wall and a first portion of the second wall form a first intersection, a second portion of the first wall and a first portion of the third wall form a second intersection, and a second portion of the second wall and a second portion of the third wall form a third intersection; and shifting the center of gravity of the golf club head by attaching first, second and third weighting elements adjacent the first, second, and third intersections, respectively, wherein the first, second and third weights are each formed of a second material which has a predetermined density that is different than the predetermined density of the first material. 